William Gilbert Chaloner. 22 November 1928—13 October 2016

Abstract

William G. Chaloner, widely known as Bill, was a world leader in the study of plant fossils. He was a pioneer in the development of palaeopalynology and helped integrate studies of macroscopic plant fossils with investigations of fossil pollen and spores. His early work expanded our understanding of Carboniferous coal-forming plants and vegetation and his investigations on the changing distributions of fossil plants contributed to improved knowledge of biogeographic patterns during the late Paleozoic, including the concept of continental drift before it was widely accepted. Bill's relentless creativity demonstrated how the fossil record of plants could be exploited to reconstruct ancient climates. He also recognized that because certain structural features of fossil leaves directly record levels of the greenhouse gas carbon dioxide they are valuable ‘biosensors’ of ancient atmospheric composition allowing investigation of the link between the greenhouse effect and past warm climates. With his clear and critical mind and grasp of diverse subject matter, Bill was adept at distilling disparate information into a coherent and understandable whole. An engaging communicator, and an unfailingly supportive mentor, he inspired many young scientists during his five decades of service to colleges of the University of London.